linux/tools/perf/builtin-lock.c

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#include "builtin.h"
#include "perf.h"
#include "util/util.h"
#include "util/cache.h"
#include "util/symbol.h"
#include "util/thread.h"
#include "util/header.h"
#include "util/parse-options.h"
#include "util/trace-event.h"
#include "util/debug.h"
#include "util/session.h"
#include <sys/types.h>
#include <sys/prctl.h>
#include <semaphore.h>
#include <pthread.h>
#include <math.h>
#include <limits.h>
#include <linux/list.h>
#include <linux/hash.h>
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
static struct perf_session *session;
/* based on kernel/lockdep.c */
#define LOCKHASH_BITS 12
#define LOCKHASH_SIZE (1UL << LOCKHASH_BITS)
static struct list_head lockhash_table[LOCKHASH_SIZE];
#define __lockhashfn(key) hash_long((unsigned long)key, LOCKHASH_BITS)
#define lockhashentry(key) (lockhash_table + __lockhashfn((key)))
struct lock_stat {
struct list_head hash_entry;
struct rb_node rb; /* used for sorting */
/*
* FIXME: raw_field_value() returns unsigned long long,
* so address of lockdep_map should be dealed as 64bit.
* Is there more better solution?
*/
void *addr; /* address of lockdep_map, used as ID */
char *name; /* for strcpy(), we cannot use const */
unsigned int nr_acquire;
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
unsigned int nr_acquired;
unsigned int nr_contended;
unsigned int nr_release;
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
unsigned int nr_readlock;
unsigned int nr_trylock;
/* these times are in nano sec. */
u64 wait_time_total;
u64 wait_time_min;
u64 wait_time_max;
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
int discard; /* flag of blacklist */
};
/*
* States of lock_seq_stat
*
* UNINITIALIZED is required for detecting first event of acquire.
* As the nature of lock events, there is no guarantee
* that the first event for the locks are acquire,
* it can be acquired, contended or release.
*/
#define SEQ_STATE_UNINITIALIZED 0 /* initial state */
#define SEQ_STATE_RELEASED 1
#define SEQ_STATE_ACQUIRING 2
#define SEQ_STATE_ACQUIRED 3
#define SEQ_STATE_READ_ACQUIRED 4
#define SEQ_STATE_CONTENDED 5
/*
* MAX_LOCK_DEPTH
* Imported from include/linux/sched.h.
* Should this be synchronized?
*/
#define MAX_LOCK_DEPTH 48
/*
* struct lock_seq_stat:
* Place to put on state of one lock sequence
* 1) acquire -> acquired -> release
* 2) acquire -> contended -> acquired -> release
* 3) acquire (with read or try) -> release
* 4) Are there other patterns?
*/
struct lock_seq_stat {
struct list_head list;
int state;
u64 prev_event_time;
void *addr;
int read_count;
};
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
struct thread_stat {
struct rb_node rb;
u32 tid;
struct list_head seq_list;
};
static struct rb_root thread_stats;
static struct thread_stat *thread_stat_find(u32 tid)
{
struct rb_node *node;
struct thread_stat *st;
node = thread_stats.rb_node;
while (node) {
st = container_of(node, struct thread_stat, rb);
if (st->tid == tid)
return st;
else if (tid < st->tid)
node = node->rb_left;
else
node = node->rb_right;
}
return NULL;
}
static void thread_stat_insert(struct thread_stat *new)
{
struct rb_node **rb = &thread_stats.rb_node;
struct rb_node *parent = NULL;
struct thread_stat *p;
while (*rb) {
p = container_of(*rb, struct thread_stat, rb);
parent = *rb;
if (new->tid < p->tid)
rb = &(*rb)->rb_left;
else if (new->tid > p->tid)
rb = &(*rb)->rb_right;
else
BUG_ON("inserting invalid thread_stat\n");
}
rb_link_node(&new->rb, parent, rb);
rb_insert_color(&new->rb, &thread_stats);
}
static struct thread_stat *thread_stat_findnew_after_first(u32 tid)
{
struct thread_stat *st;
st = thread_stat_find(tid);
if (st)
return st;
st = zalloc(sizeof(struct thread_stat));
if (!st)
die("memory allocation failed\n");
st->tid = tid;
INIT_LIST_HEAD(&st->seq_list);
thread_stat_insert(st);
return st;
}
static struct thread_stat *thread_stat_findnew_first(u32 tid);
static struct thread_stat *(*thread_stat_findnew)(u32 tid) =
thread_stat_findnew_first;
static struct thread_stat *thread_stat_findnew_first(u32 tid)
{
struct thread_stat *st;
st = zalloc(sizeof(struct thread_stat));
if (!st)
die("memory allocation failed\n");
st->tid = tid;
INIT_LIST_HEAD(&st->seq_list);
rb_link_node(&st->rb, NULL, &thread_stats.rb_node);
rb_insert_color(&st->rb, &thread_stats);
thread_stat_findnew = thread_stat_findnew_after_first;
return st;
}
/* build simple key function one is bigger than two */
#define SINGLE_KEY(member) \
static int lock_stat_key_ ## member(struct lock_stat *one, \
struct lock_stat *two) \
{ \
return one->member > two->member; \
}
SINGLE_KEY(nr_acquired)
SINGLE_KEY(nr_contended)
SINGLE_KEY(wait_time_total)
SINGLE_KEY(wait_time_min)
SINGLE_KEY(wait_time_max)
struct lock_key {
/*
* name: the value for specify by user
* this should be simpler than raw name of member
* e.g. nr_acquired -> acquired, wait_time_total -> wait_total
*/
const char *name;
int (*key)(struct lock_stat*, struct lock_stat*);
};
static const char *sort_key = "acquired";
static int (*compare)(struct lock_stat *, struct lock_stat *);
static struct rb_root result; /* place to store sorted data */
#define DEF_KEY_LOCK(name, fn_suffix) \
{ #name, lock_stat_key_ ## fn_suffix }
struct lock_key keys[] = {
DEF_KEY_LOCK(acquired, nr_acquired),
DEF_KEY_LOCK(contended, nr_contended),
DEF_KEY_LOCK(wait_total, wait_time_total),
DEF_KEY_LOCK(wait_min, wait_time_min),
DEF_KEY_LOCK(wait_max, wait_time_max),
/* extra comparisons much complicated should be here */
{ NULL, NULL }
};
static void select_key(void)
{
int i;
for (i = 0; keys[i].name; i++) {
if (!strcmp(keys[i].name, sort_key)) {
compare = keys[i].key;
return;
}
}
die("Unknown compare key:%s\n", sort_key);
}
static void insert_to_result(struct lock_stat *st,
int (*bigger)(struct lock_stat *, struct lock_stat *))
{
struct rb_node **rb = &result.rb_node;
struct rb_node *parent = NULL;
struct lock_stat *p;
while (*rb) {
p = container_of(*rb, struct lock_stat, rb);
parent = *rb;
if (bigger(st, p))
rb = &(*rb)->rb_left;
else
rb = &(*rb)->rb_right;
}
rb_link_node(&st->rb, parent, rb);
rb_insert_color(&st->rb, &result);
}
/* returns left most element of result, and erase it */
static struct lock_stat *pop_from_result(void)
{
struct rb_node *node = result.rb_node;
if (!node)
return NULL;
while (node->rb_left)
node = node->rb_left;
rb_erase(node, &result);
return container_of(node, struct lock_stat, rb);
}
static struct lock_stat *lock_stat_findnew(void *addr, const char *name)
{
struct list_head *entry = lockhashentry(addr);
struct lock_stat *ret, *new;
list_for_each_entry(ret, entry, hash_entry) {
if (ret->addr == addr)
return ret;
}
new = zalloc(sizeof(struct lock_stat));
if (!new)
goto alloc_failed;
new->addr = addr;
new->name = zalloc(sizeof(char) * strlen(name) + 1);
if (!new->name)
goto alloc_failed;
strcpy(new->name, name);
new->wait_time_min = ULLONG_MAX;
list_add(&new->hash_entry, entry);
return new;
alloc_failed:
die("memory allocation failed\n");
}
static char const *input_name = "perf.data";
static int profile_cpu = -1;
struct raw_event_sample {
u32 size;
char data[0];
};
struct trace_acquire_event {
void *addr;
const char *name;
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
int flag;
};
struct trace_acquired_event {
void *addr;
const char *name;
};
struct trace_contended_event {
void *addr;
const char *name;
};
struct trace_release_event {
void *addr;
const char *name;
};
struct trace_lock_handler {
void (*acquire_event)(struct trace_acquire_event *,
struct event *,
int cpu,
u64 timestamp,
struct thread *thread);
void (*acquired_event)(struct trace_acquired_event *,
struct event *,
int cpu,
u64 timestamp,
struct thread *thread);
void (*contended_event)(struct trace_contended_event *,
struct event *,
int cpu,
u64 timestamp,
struct thread *thread);
void (*release_event)(struct trace_release_event *,
struct event *,
int cpu,
u64 timestamp,
struct thread *thread);
};
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
static struct lock_seq_stat *get_seq(struct thread_stat *ts, void *addr)
{
struct lock_seq_stat *seq;
list_for_each_entry(seq, &ts->seq_list, list) {
if (seq->addr == addr)
return seq;
}
seq = zalloc(sizeof(struct lock_seq_stat));
if (!seq)
die("Not enough memory\n");
seq->state = SEQ_STATE_UNINITIALIZED;
seq->addr = addr;
list_add(&seq->list, &ts->seq_list);
return seq;
}
static int bad_hist[4];
static void
report_lock_acquire_event(struct trace_acquire_event *acquire_event,
struct event *__event __used,
int cpu __used,
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
u64 timestamp __used,
struct thread *thread __used)
{
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
struct lock_stat *ls;
struct thread_stat *ts;
struct lock_seq_stat *seq;
ls = lock_stat_findnew(acquire_event->addr, acquire_event->name);
if (ls->discard)
return;
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
ts = thread_stat_findnew(thread->pid);
seq = get_seq(ts, acquire_event->addr);
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
switch (seq->state) {
case SEQ_STATE_UNINITIALIZED:
case SEQ_STATE_RELEASED:
if (!acquire_event->flag) {
seq->state = SEQ_STATE_ACQUIRING;
} else {
if (acquire_event->flag & 1)
ls->nr_trylock++;
if (acquire_event->flag & 2)
ls->nr_readlock++;
seq->state = SEQ_STATE_READ_ACQUIRED;
seq->read_count = 1;
ls->nr_acquired++;
}
break;
case SEQ_STATE_READ_ACQUIRED:
if (acquire_event->flag & 2) {
seq->read_count++;
ls->nr_acquired++;
goto end;
} else {
goto broken;
}
break;
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
case SEQ_STATE_ACQUIRED:
case SEQ_STATE_ACQUIRING:
case SEQ_STATE_CONTENDED:
broken:
/* broken lock sequence, discard it */
ls->discard = 1;
bad_hist[0]++;
list_del(&seq->list);
free(seq);
goto end;
break;
default:
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
BUG_ON("Unknown state of lock sequence found!\n");
break;
}
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
ls->nr_acquire++;
seq->prev_event_time = timestamp;
end:
return;
}
static void
report_lock_acquired_event(struct trace_acquired_event *acquired_event,
struct event *__event __used,
int cpu __used,
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
u64 timestamp __used,
struct thread *thread __used)
{
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
struct lock_stat *ls;
struct thread_stat *ts;
struct lock_seq_stat *seq;
u64 contended_term;
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
ls = lock_stat_findnew(acquired_event->addr, acquired_event->name);
if (ls->discard)
return;
ts = thread_stat_findnew(thread->pid);
seq = get_seq(ts, acquired_event->addr);
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
switch (seq->state) {
case SEQ_STATE_UNINITIALIZED:
/* orphan event, do nothing */
return;
case SEQ_STATE_ACQUIRING:
break;
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
case SEQ_STATE_CONTENDED:
contended_term = timestamp - seq->prev_event_time;
ls->wait_time_total += contended_term;
if (contended_term < ls->wait_time_min)
ls->wait_time_min = contended_term;
else if (ls->wait_time_max < contended_term)
ls->wait_time_max = contended_term;
break;
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
case SEQ_STATE_RELEASED:
case SEQ_STATE_ACQUIRED:
case SEQ_STATE_READ_ACQUIRED:
/* broken lock sequence, discard it */
ls->discard = 1;
bad_hist[1]++;
list_del(&seq->list);
free(seq);
goto end;
break;
default:
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
BUG_ON("Unknown state of lock sequence found!\n");
break;
}
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
seq->state = SEQ_STATE_ACQUIRED;
ls->nr_acquired++;
seq->prev_event_time = timestamp;
end:
return;
}
static void
report_lock_contended_event(struct trace_contended_event *contended_event,
struct event *__event __used,
int cpu __used,
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
u64 timestamp __used,
struct thread *thread __used)
{
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
struct lock_stat *ls;
struct thread_stat *ts;
struct lock_seq_stat *seq;
ls = lock_stat_findnew(contended_event->addr, contended_event->name);
if (ls->discard)
return;
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
ts = thread_stat_findnew(thread->pid);
seq = get_seq(ts, contended_event->addr);
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
switch (seq->state) {
case SEQ_STATE_UNINITIALIZED:
/* orphan event, do nothing */
return;
case SEQ_STATE_ACQUIRING:
break;
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
case SEQ_STATE_RELEASED:
case SEQ_STATE_ACQUIRED:
case SEQ_STATE_READ_ACQUIRED:
case SEQ_STATE_CONTENDED:
/* broken lock sequence, discard it */
ls->discard = 1;
bad_hist[2]++;
list_del(&seq->list);
free(seq);
goto end;
break;
default:
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
BUG_ON("Unknown state of lock sequence found!\n");
break;
}
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
seq->state = SEQ_STATE_CONTENDED;
ls->nr_contended++;
seq->prev_event_time = timestamp;
end:
return;
}
static void
report_lock_release_event(struct trace_release_event *release_event,
struct event *__event __used,
int cpu __used,
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
u64 timestamp __used,
struct thread *thread __used)
{
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
struct lock_stat *ls;
struct thread_stat *ts;
struct lock_seq_stat *seq;
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
ls = lock_stat_findnew(release_event->addr, release_event->name);
if (ls->discard)
return;
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
ts = thread_stat_findnew(thread->pid);
seq = get_seq(ts, release_event->addr);
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
switch (seq->state) {
case SEQ_STATE_UNINITIALIZED:
goto end;
break;
case SEQ_STATE_ACQUIRED:
break;
case SEQ_STATE_READ_ACQUIRED:
seq->read_count--;
BUG_ON(seq->read_count < 0);
if (!seq->read_count) {
ls->nr_release++;
goto end;
}
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
break;
case SEQ_STATE_ACQUIRING:
case SEQ_STATE_CONTENDED:
case SEQ_STATE_RELEASED:
/* broken lock sequence, discard it */
ls->discard = 1;
bad_hist[3]++;
goto free_seq;
break;
default:
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
BUG_ON("Unknown state of lock sequence found!\n");
break;
}
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
ls->nr_release++;
free_seq:
list_del(&seq->list);
free(seq);
end:
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
return;
}
/* lock oriented handlers */
/* TODO: handlers for CPU oriented, thread oriented */
static struct trace_lock_handler report_lock_ops = {
.acquire_event = report_lock_acquire_event,
.acquired_event = report_lock_acquired_event,
.contended_event = report_lock_contended_event,
.release_event = report_lock_release_event,
};
static struct trace_lock_handler *trace_handler;
static void
process_lock_acquire_event(void *data,
struct event *event __used,
int cpu __used,
u64 timestamp __used,
struct thread *thread __used)
{
struct trace_acquire_event acquire_event;
u64 tmp; /* this is required for casting... */
tmp = raw_field_value(event, "lockdep_addr", data);
memcpy(&acquire_event.addr, &tmp, sizeof(void *));
acquire_event.name = (char *)raw_field_ptr(event, "name", data);
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
acquire_event.flag = (int)raw_field_value(event, "flag", data);
if (trace_handler->acquire_event)
trace_handler->acquire_event(&acquire_event, event, cpu, timestamp, thread);
}
static void
process_lock_acquired_event(void *data,
struct event *event __used,
int cpu __used,
u64 timestamp __used,
struct thread *thread __used)
{
struct trace_acquired_event acquired_event;
u64 tmp; /* this is required for casting... */
tmp = raw_field_value(event, "lockdep_addr", data);
memcpy(&acquired_event.addr, &tmp, sizeof(void *));
acquired_event.name = (char *)raw_field_ptr(event, "name", data);
if (trace_handler->acquire_event)
trace_handler->acquired_event(&acquired_event, event, cpu, timestamp, thread);
}
static void
process_lock_contended_event(void *data,
struct event *event __used,
int cpu __used,
u64 timestamp __used,
struct thread *thread __used)
{
struct trace_contended_event contended_event;
u64 tmp; /* this is required for casting... */
tmp = raw_field_value(event, "lockdep_addr", data);
memcpy(&contended_event.addr, &tmp, sizeof(void *));
contended_event.name = (char *)raw_field_ptr(event, "name", data);
if (trace_handler->acquire_event)
trace_handler->contended_event(&contended_event, event, cpu, timestamp, thread);
}
static void
process_lock_release_event(void *data,
struct event *event __used,
int cpu __used,
u64 timestamp __used,
struct thread *thread __used)
{
struct trace_release_event release_event;
u64 tmp; /* this is required for casting... */
tmp = raw_field_value(event, "lockdep_addr", data);
memcpy(&release_event.addr, &tmp, sizeof(void *));
release_event.name = (char *)raw_field_ptr(event, "name", data);
if (trace_handler->acquire_event)
trace_handler->release_event(&release_event, event, cpu, timestamp, thread);
}
static void
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
process_raw_event(void *data, int cpu __used,
u64 timestamp __used, struct thread *thread __used)
{
struct event *event;
int type;
type = trace_parse_common_type(data);
event = trace_find_event(type);
if (!strcmp(event->name, "lock_acquire"))
process_lock_acquire_event(data, event, cpu, timestamp, thread);
if (!strcmp(event->name, "lock_acquired"))
process_lock_acquired_event(data, event, cpu, timestamp, thread);
if (!strcmp(event->name, "lock_contended"))
process_lock_contended_event(data, event, cpu, timestamp, thread);
if (!strcmp(event->name, "lock_release"))
process_lock_release_event(data, event, cpu, timestamp, thread);
}
perf lock: Drop the buffers multiplexing dependency We need to deal with time ordered events to build a correct state machine of lock events. This is why we multiplex the lock events buffers. But the ordering is done from the kernel, on the tracing fast path, leading to high contention between cpus. Without multiplexing, the events appears in a weak order. If we have four events, each split per cpu, perf record will read the events buffers in the following order: [ CPU0 ev0, CPU0 ev1, CPU0 ev3, CPU0 ev4, CPU1 ev0, CPU1 ev0....] To handle a post processing reordering, we could just read and sort the whole in memory, but it just doesn't scale with high amounts of events: lock events can fill huge amounts in few times. Basically we need to sort in memory and find a "grace period" point when we know that a given slice of previously sorted events can be committed for post-processing, so that we can unload the memory usage step by step and keep a scalable sorting list. There is no strong rules about how to define such "grace period". What does this patch is: We define a FLUSH_PERIOD value that defines a grace period in seconds. We want to have a slice of events covering 2 * FLUSH_PERIOD in our sorted list. If FLUSH_PERIOD is big enough, it ensures every events that occured in the first half of the timeslice have all been buffered and there are none remaining and there won't be further to put inside this first timeslice. Then once we reach the 2 * FLUSH_PERIOD timeslice, we flush the first half to be gentle with the memory (the second half can still get new events in the middle, so wait another period to flush it) FLUSH_PERIOD is defined to 5 seconds. Say the first event started on time t0. We can safely assume that at the time we are processing events of t0 + 10 seconds, ther won't be anymore events to read from perf.data that occured between t0 and t0 + 5 seconds. Hence we can safely flush the first half. To point out funky bugs, we have a guardian that checks a new event timestamp is not below the last event's timestamp flushed and that displays a warning in this case. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com>
2010-02-03 16:09:33 +08:00
struct raw_event_queue {
u64 timestamp;
int cpu;
void *data;
struct thread *thread;
struct list_head list;
};
static LIST_HEAD(raw_event_head);
#define FLUSH_PERIOD (5 * NSEC_PER_SEC)
static u64 flush_limit = ULLONG_MAX;
static u64 last_flush = 0;
struct raw_event_queue *last_inserted;
static void flush_raw_event_queue(u64 limit)
{
struct raw_event_queue *tmp, *iter;
list_for_each_entry_safe(iter, tmp, &raw_event_head, list) {
if (iter->timestamp > limit)
return;
if (iter == last_inserted)
last_inserted = NULL;
process_raw_event(iter->data, iter->cpu, iter->timestamp,
iter->thread);
last_flush = iter->timestamp;
list_del(&iter->list);
free(iter->data);
free(iter);
}
}
static void __queue_raw_event_end(struct raw_event_queue *new)
{
struct raw_event_queue *iter;
list_for_each_entry_reverse(iter, &raw_event_head, list) {
if (iter->timestamp < new->timestamp) {
list_add(&new->list, &iter->list);
return;
}
}
list_add(&new->list, &raw_event_head);
}
static void __queue_raw_event_before(struct raw_event_queue *new,
struct raw_event_queue *iter)
{
list_for_each_entry_continue_reverse(iter, &raw_event_head, list) {
if (iter->timestamp < new->timestamp) {
list_add(&new->list, &iter->list);
return;
}
}
list_add(&new->list, &raw_event_head);
}
static void __queue_raw_event_after(struct raw_event_queue *new,
struct raw_event_queue *iter)
{
list_for_each_entry_continue(iter, &raw_event_head, list) {
if (iter->timestamp > new->timestamp) {
list_add_tail(&new->list, &iter->list);
return;
}
}
list_add_tail(&new->list, &raw_event_head);
}
/* The queue is ordered by time */
static void __queue_raw_event(struct raw_event_queue *new)
{
if (!last_inserted) {
__queue_raw_event_end(new);
return;
}
/*
* Most of the time the current event has a timestamp
* very close to the last event inserted, unless we just switched
* to another event buffer. Having a sorting based on a list and
* on the last inserted event that is close to the current one is
* probably more efficient than an rbtree based sorting.
*/
if (last_inserted->timestamp >= new->timestamp)
__queue_raw_event_before(new, last_inserted);
else
__queue_raw_event_after(new, last_inserted);
}
static void queue_raw_event(void *data, int raw_size, int cpu,
u64 timestamp, struct thread *thread)
{
struct raw_event_queue *new;
if (flush_limit == ULLONG_MAX)
flush_limit = timestamp + FLUSH_PERIOD;
if (timestamp < last_flush) {
printf("Warning: Timestamp below last timeslice flush\n");
return;
}
new = malloc(sizeof(*new));
if (!new)
die("Not enough memory\n");
new->timestamp = timestamp;
new->cpu = cpu;
new->thread = thread;
new->data = malloc(raw_size);
if (!new->data)
die("Not enough memory\n");
memcpy(new->data, data, raw_size);
__queue_raw_event(new);
last_inserted = new;
/*
* We want to have a slice of events covering 2 * FLUSH_PERIOD
* If FLUSH_PERIOD is big enough, it ensures every events that occured
* in the first half of the timeslice have all been buffered and there
* are none remaining (we need that because of the weakly ordered
* event recording we have). Then once we reach the 2 * FLUSH_PERIOD
* timeslice, we flush the first half to be gentle with the memory
* (the second half can still get new events in the middle, so wait
* another period to flush it)
*/
if (new->timestamp > flush_limit &&
new->timestamp - flush_limit > FLUSH_PERIOD) {
flush_limit += FLUSH_PERIOD;
flush_raw_event_queue(flush_limit);
}
}
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
static int process_sample_event(event_t *event, struct perf_session *s)
{
struct thread *thread;
struct sample_data data;
bzero(&data, sizeof(struct sample_data));
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
event__parse_sample(event, s->sample_type, &data);
/* CAUTION: using tid as thread.pid */
thread = perf_session__findnew(s, data.tid);
if (thread == NULL) {
pr_debug("problem processing %d event, skipping it.\n",
event->header.type);
return -1;
}
dump_printf(" ... thread: %s:%d\n", thread->comm, thread->pid);
if (profile_cpu != -1 && profile_cpu != (int) data.cpu)
return 0;
perf lock: Drop the buffers multiplexing dependency We need to deal with time ordered events to build a correct state machine of lock events. This is why we multiplex the lock events buffers. But the ordering is done from the kernel, on the tracing fast path, leading to high contention between cpus. Without multiplexing, the events appears in a weak order. If we have four events, each split per cpu, perf record will read the events buffers in the following order: [ CPU0 ev0, CPU0 ev1, CPU0 ev3, CPU0 ev4, CPU1 ev0, CPU1 ev0....] To handle a post processing reordering, we could just read and sort the whole in memory, but it just doesn't scale with high amounts of events: lock events can fill huge amounts in few times. Basically we need to sort in memory and find a "grace period" point when we know that a given slice of previously sorted events can be committed for post-processing, so that we can unload the memory usage step by step and keep a scalable sorting list. There is no strong rules about how to define such "grace period". What does this patch is: We define a FLUSH_PERIOD value that defines a grace period in seconds. We want to have a slice of events covering 2 * FLUSH_PERIOD in our sorted list. If FLUSH_PERIOD is big enough, it ensures every events that occured in the first half of the timeslice have all been buffered and there are none remaining and there won't be further to put inside this first timeslice. Then once we reach the 2 * FLUSH_PERIOD timeslice, we flush the first half to be gentle with the memory (the second half can still get new events in the middle, so wait another period to flush it) FLUSH_PERIOD is defined to 5 seconds. Say the first event started on time t0. We can safely assume that at the time we are processing events of t0 + 10 seconds, ther won't be anymore events to read from perf.data that occured between t0 and t0 + 5 seconds. Hence we can safely flush the first half. To point out funky bugs, we have a guardian that checks a new event timestamp is not below the last event's timestamp flushed and that displays a warning in this case. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com>
2010-02-03 16:09:33 +08:00
queue_raw_event(data.raw_data, data.raw_size, data.cpu, data.time, thread);
return 0;
}
/* TODO: various way to print, coloring, nano or milli sec */
static void print_result(void)
{
struct lock_stat *st;
char cut_name[20];
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
int bad, total;
printf("%20s ", "Name");
printf("%10s ", "acquired");
printf("%10s ", "contended");
printf("%15s ", "total wait (ns)");
printf("%15s ", "max wait (ns)");
printf("%15s ", "min wait (ns)");
printf("\n\n");
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
bad = total = 0;
while ((st = pop_from_result())) {
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
total++;
if (st->discard) {
bad++;
continue;
}
bzero(cut_name, 20);
if (strlen(st->name) < 16) {
/* output raw name */
printf("%20s ", st->name);
} else {
strncpy(cut_name, st->name, 16);
cut_name[16] = '.';
cut_name[17] = '.';
cut_name[18] = '.';
cut_name[19] = '\0';
/* cut off name for saving output style */
printf("%20s ", cut_name);
}
printf("%10u ", st->nr_acquired);
printf("%10u ", st->nr_contended);
printf("%15llu ", st->wait_time_total);
printf("%15llu ", st->wait_time_max);
printf("%15llu ", st->wait_time_min == ULLONG_MAX ?
0 : st->wait_time_min);
printf("\n");
}
perf lock: Fix state machine to recognize lock sequence Previous state machine of perf lock was really broken. This patch improves it a little. This patch prepares the list of state machine that represents lock sequences for each threads. These state machines can be one of these sequences: 1) acquire -> acquired -> release 2) acquire -> contended -> acquired -> release 3) acquire (w/ try) -> release 4) acquire (w/ read) -> release The case of 4) is a little special. Double acquire of read lock is allowed, so the state machine counts read lock number, and permits double acquire and release. But, things are not so simple. Something in my model is still wrong. I counted the number of lock instances with bad sequence, and ratio is like this (case of tracing whoami): bad:233, total:2279 version 2: * threads are now identified with tid, not pid * prepared SEQ_STATE_READ_ACQUIRED for read lock. * bunch of struct lock_seq_stat is now linked list * debug information enhanced (this have to be removed someday) e.g. | === output for debug=== | | bad:233, total:2279 | bad rate:0.000000 | histogram of events caused bad sequence | acquire: 165 | acquired: 0 | contended: 0 | release: 68 Signed-off-by: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> LKML-Reference: <1271852634-9351-1-git-send-email-mitake@dcl.info.waseda.ac.jp> [rename SEQ_STATE_UNINITED to SEQ_STATE_UNINITIALIZED] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
2010-04-21 20:23:54 +08:00
{
/* Output for debug, this have to be removed */
int i;
const char *name[4] =
{ "acquire", "acquired", "contended", "release" };
printf("\n=== output for debug===\n\n");
printf("bad:%d, total:%d\n", bad, total);
printf("bad rate:%f\n", (double)(bad / total));
printf("histogram of events caused bad sequence\n");
for (i = 0; i < 4; i++)
printf(" %10s: %d\n", name[i], bad_hist[i]);
}
}
static void dump_map(void)
{
unsigned int i;
struct lock_stat *st;
for (i = 0; i < LOCKHASH_SIZE; i++) {
list_for_each_entry(st, &lockhash_table[i], hash_entry) {
printf("%p: %s\n", st->addr, st->name);
}
}
}
static struct perf_event_ops eops = {
.sample = process_sample_event,
.comm = event__process_comm,
};
static int read_events(void)
{
session = perf_session__new(input_name, O_RDONLY, 0);
if (!session)
die("Initializing perf session failed\n");
return perf_session__process_events(session, &eops);
}
static void sort_result(void)
{
unsigned int i;
struct lock_stat *st;
for (i = 0; i < LOCKHASH_SIZE; i++) {
list_for_each_entry(st, &lockhash_table[i], hash_entry) {
insert_to_result(st, compare);
}
}
}
static void __cmd_report(void)
{
setup_pager();
select_key();
read_events();
perf lock: Drop the buffers multiplexing dependency We need to deal with time ordered events to build a correct state machine of lock events. This is why we multiplex the lock events buffers. But the ordering is done from the kernel, on the tracing fast path, leading to high contention between cpus. Without multiplexing, the events appears in a weak order. If we have four events, each split per cpu, perf record will read the events buffers in the following order: [ CPU0 ev0, CPU0 ev1, CPU0 ev3, CPU0 ev4, CPU1 ev0, CPU1 ev0....] To handle a post processing reordering, we could just read and sort the whole in memory, but it just doesn't scale with high amounts of events: lock events can fill huge amounts in few times. Basically we need to sort in memory and find a "grace period" point when we know that a given slice of previously sorted events can be committed for post-processing, so that we can unload the memory usage step by step and keep a scalable sorting list. There is no strong rules about how to define such "grace period". What does this patch is: We define a FLUSH_PERIOD value that defines a grace period in seconds. We want to have a slice of events covering 2 * FLUSH_PERIOD in our sorted list. If FLUSH_PERIOD is big enough, it ensures every events that occured in the first half of the timeslice have all been buffered and there are none remaining and there won't be further to put inside this first timeslice. Then once we reach the 2 * FLUSH_PERIOD timeslice, we flush the first half to be gentle with the memory (the second half can still get new events in the middle, so wait another period to flush it) FLUSH_PERIOD is defined to 5 seconds. Say the first event started on time t0. We can safely assume that at the time we are processing events of t0 + 10 seconds, ther won't be anymore events to read from perf.data that occured between t0 and t0 + 5 seconds. Hence we can safely flush the first half. To point out funky bugs, we have a guardian that checks a new event timestamp is not below the last event's timestamp flushed and that displays a warning in this case. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Jens Axboe <jens.axboe@oracle.com>
2010-02-03 16:09:33 +08:00
flush_raw_event_queue(ULLONG_MAX);
sort_result();
print_result();
}
static const char * const report_usage[] = {
"perf lock report [<options>]",
NULL
};
static const struct option report_options[] = {
OPT_STRING('k', "key", &sort_key, "acquired",
"key for sorting"),
/* TODO: type */
OPT_END()
};
static const char * const lock_usage[] = {
"perf lock [<options>] {record|trace|report}",
NULL
};
static const struct option lock_options[] = {
OPT_STRING('i', "input", &input_name, "file", "input file name"),
perf: Fix endianness argument compatibility with OPT_BOOLEAN() and introduce OPT_INCR() Parsing an option from the command line with OPT_BOOLEAN on a bool data type would not work on a big-endian machine due to the manner in which the boolean was being cast into an int and incremented. For example, running 'perf probe --list' on a PowerPC machine would fail to properly set the list_events bool and would therefore print out the usage information and terminate. This patch makes OPT_BOOLEAN work as expected with a bool datatype. For cases where the original OPT_BOOLEAN was intentionally being used to increment an int each time it was passed in on the command line, this patch introduces OPT_INCR with the old behaviour of OPT_BOOLEAN (the verbose variable is currently the only such example of this). I have reviewed every use of OPT_BOOLEAN to verify that a true C99 bool was passed. Where integers were used, I verified that they were only being used for boolean logic and changed them to bools to ensure that they would not be mistakenly used as ints. The major exception was the verbose variable which now uses OPT_INCR instead of OPT_BOOLEAN. Signed-off-by: Ian Munsie <imunsie@au.ibm.com> Acked-by: David S. Miller <davem@davemloft.net> Cc: <stable@kernel.org> # NOTE: wont apply to .3[34].x cleanly, please backport Cc: Git development list <git@vger.kernel.org> Cc: Ian Munsie <imunsie@au1.ibm.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Eric B Munson <ebmunson@us.ibm.com> Cc: Valdis.Kletnieks@vt.edu Cc: WANG Cong <amwang@redhat.com> Cc: Thiago Farina <tfransosi@gmail.com> Cc: Masami Hiramatsu <mhiramat@redhat.com> Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com> Cc: Jaswinder Singh Rajput <jaswinderrajput@gmail.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Mike Galbraith <efault@gmx.de> Cc: Tom Zanussi <tzanussi@gmail.com> Cc: Anton Blanchard <anton@samba.org> Cc: John Kacur <jkacur@redhat.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> LKML-Reference: <1271147857-11604-1-git-send-email-imunsie@au.ibm.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-04-13 16:37:33 +08:00
OPT_INCR('v', "verbose", &verbose, "be more verbose (show symbol address, etc)"),
OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace, "dump raw trace in ASCII"),
OPT_END()
};
static const char *record_args[] = {
"record",
"-a",
"-R",
"-f",
"-m", "1024",
"-c", "1",
"-e", "lock:lock_acquire:r",
"-e", "lock:lock_acquired:r",
"-e", "lock:lock_contended:r",
"-e", "lock:lock_release:r",
};
static int __cmd_record(int argc, const char **argv)
{
unsigned int rec_argc, i, j;
const char **rec_argv;
rec_argc = ARRAY_SIZE(record_args) + argc - 1;
rec_argv = calloc(rec_argc + 1, sizeof(char *));
for (i = 0; i < ARRAY_SIZE(record_args); i++)
rec_argv[i] = strdup(record_args[i]);
for (j = 1; j < (unsigned int)argc; j++, i++)
rec_argv[i] = argv[j];
BUG_ON(i != rec_argc);
return cmd_record(i, rec_argv, NULL);
}
int cmd_lock(int argc, const char **argv, const char *prefix __used)
{
unsigned int i;
symbol__init();
for (i = 0; i < LOCKHASH_SIZE; i++)
INIT_LIST_HEAD(lockhash_table + i);
argc = parse_options(argc, argv, lock_options, lock_usage,
PARSE_OPT_STOP_AT_NON_OPTION);
if (!argc)
usage_with_options(lock_usage, lock_options);
if (!strncmp(argv[0], "rec", 3)) {
return __cmd_record(argc, argv);
} else if (!strncmp(argv[0], "report", 6)) {
trace_handler = &report_lock_ops;
if (argc) {
argc = parse_options(argc, argv,
report_options, report_usage, 0);
if (argc)
usage_with_options(report_usage, report_options);
}
__cmd_report();
} else if (!strcmp(argv[0], "trace")) {
/* Aliased to 'perf trace' */
return cmd_trace(argc, argv, prefix);
} else if (!strcmp(argv[0], "map")) {
/* recycling report_lock_ops */
trace_handler = &report_lock_ops;
setup_pager();
read_events();
dump_map();
} else {
usage_with_options(lock_usage, lock_options);
}
return 0;
}